There is a huge market for color photosensors, particularly for use in electronic cameras. In 2013, the market is dominated by cameras having a single photosensor array integrated circuit. Each photosensor of the array typically has a photodiode sensor, together with ancillary circuitry for precharging and reading the photodiodes. The majority of photosensor arrays used in cameras use three patterned color filter layers in a repeated, or tiled, pattern over individual photosensors of the array such that the array has a pattern of photosensors sensitive to at least three colors of incident light, as illustrated in FIG. 1, illustrating a red 102, blue 104, and green 106—sensitive photo sensor with a red 108 filter over the red sensor, a blue filter 110 over the blue sensor, and a green filter 112 over the green sensor. Typically, the photodiodes have a second contact in substrate 114. Many of these photosensor arrays, known as Bayer-pattern sensors, have the photosensors organized in rectangular patterns on the array.
Many such photosensor arrays include an array of microlenses 116, with an individual microlens over the filter of each photosensor of the array. In order to prevent interference by stray light interacting with ancillary circuitry of the array, there may be an opaque mask 118 over portions of the silicon surface 120 between photodiodes and over ancillary circuitry. For simplicity, ancillary circuitry of each pixel and of the array are not shown in FIG. 1.